mild cognitive impairment, or mci, is significant forgetfulness but not severe enough to interfere with daily life. >> this was a surprising finding to us. >> reporter: what also makes these new findings so surprising is women are more likely than men to get alzheimer's. fortunately for leif, his wife's memory is still intact. >> i try to remember to ask him daily, morning and evening, if he has taken his medication. >> reporter: doctors aren't sure why men are experiencing this memory loss more than women. but they're looking very closely at a possible clue. heart disease. >> when we look at the men who have mild cognitive impairment, they tend to have more of the vascular risk factors than women do. such as high blood pressure, diabetes, smoking history. >> reporter: the good news is these are areas where doctors can intervene and potentially diminish the risk of developing significant memory loss. linsey davis, abc news, new york. >> of course there's so many theories for the differences. jim our floor director had one. he said these men are forgetting more things because there are w